Fuel control apparatus



Sept. 12, 1944. F, SCHAFER ET AL 2,358,255

FUEL CONTROL APPARATUS I Filed July 6, 1942 3 Sheets-Sheet 1 FROM GASSUPPLY TANK TO H lA/TAKE MAN/FOLD Q Hi 1| Pm V n 5, 0 /o I INVENTORS.

Sept. 12, 1944. F. SCHAFER ETAL 27,353,255

FUEL CONTROL APPARATUS Filed July 6, 1942 :5 sheets-sheet 2 II I I I I I20 1 I. A III II" I 1 II" 2a 22 R W V T J g. H 1/ H 7 0 //VTA/(E NANSept. 12, 1944. SCHAFER 1- AL 2,358,255

. FUEL CONTROL APPARATUS Filed July 6, 1942 V 5 Sheets-Shet 5 "I. null/7 INVENTORS.

Patented Sept. 12, 1944 Schafer,

Duluth, Minn.;

[23582. 5 d FUEL ooN'rRoL m ners" 3 Frank Schafer, Oshkosh, Wis.', a'ndI-Ierman It:

said Herman R.

Schafer assignor to said Frank Schafer Application July 6, 1942, SerialNo. 451,188

1 Claim. (01. 26172) This invention relates to apparatus for controllingthe fuel supply for internal combustion engines, particularly such asare used in connection with motor vehicles and thelike.

It is well known that during periods when suc a motor vehicle is movingalong a level highway with not so much demand for fuel to maintain thespeed desired as to lower the vacuum pressure, or when coasting downgrade with the throttle closed and the clutch engaged, harmful fuelwastes occur through both the main and idling jets of the carburetor,with the result that unburned and partially burned fuel is exhausted,giving ofi disagreeable odors and fouling the cylinders, exhaust lineand mufller, as well as materially lessening the mileage obtained by thevehicle per gallon of fuel. This condition occurs with particularfrequency in heavy traffic, on hills, and on long trips. It has beenfound possible to eliminate for the most part these undesirableconditions by cutting ofi or lessening the supply'of fuel to the engineduring such periods, thereby effecting marked improvements in efliciencyand economy in operation of the motor vehicle.

Consequently it is the principal object of the present invention toprovide such a device for the control of fuel to the engine in a mannerthat will substantially eliminate all exhaust of unburned or partiallyunburned gases.

Other objects and advantages of the invention will appear in thefollowing description thereof.

Referring now to the accompanying drawings, forming part of thisapplication, and wherein like reference characters indicate like parts:

Fig. 1 is a top plan view of one embodiment of the invention. Fig. 2 isa side elevation, partly in section, of Fig. 1, and Figs. 3 and 4 arecentral vertical sections through a slightly modified assembly toillustrate more clearly the extreme relative position of the parts.

The embodiment of the invention here shown and in which the gasreceiving bowl of the carburetor is separated from the mixing chamberthereof, the float carrying bowl is illustrated at 2, while the mixingchamber of the carburetor is shown at I; this latter having attachedthereto the air inlet connection 3 having the usual butterfly valve 4therein, and the throttle control valve 5, within the connection 20 tothe intake manifold of the engine.

The'gas intake connection to the bowl 2 is illustrated at 6, and theconnection between the bowl 2 and the mixing chamber is shown at I andin this instance the connection is shown somewhat extended to provideample flexibility between the separated members of the carburetor sothat the bowl 2 may readily reciprocate vertically, the object of whichwill be described later.

In this novel construction, the bowl 2 of the carburetor is mounted onone portion of a suitable foundation member or bracket 8 which is commonto both portions of the carburetor, and,

as guiding means for the bowl, I have illustrated four upright posts 99and Ill-Ii], they being fixed to the bracket 8 as by beingscrew-threaded thereinto, or otherwise as desired.

Directly beneath the bowl 2 and also fixed to the bracket 8 is thediaphragm valve ll, having the ordinary resilient valve member l2therein to which is centrally fixed the upstanding stem I3,

the upper end of which is removably attached in any desired manner tothe bottom of the bowl 2. The lower central portion of the valve H hasfixed thereto the somewhat elongated connection I4, having the removableplug member l5 screwthreadedly mounted within the free end thereof toprovide a convenient support for the expansive helical spring l6, whichlatter is designed to assist in urging the yieldable member l2 at alltimes. to its uppermost position to insure the vertical relation ofthetwo portions of the carburetor t and 2 being properly positioned fornormal operation of the carburetor.

Within the plug I5 is attached a suitable connection ll leading to theintake manifold of the engine, not shown, but deemed suflicientlyobvious to those versed in the art, to providethe required vacuum forproper operation of the device.

With such connection properly established, it

is apparent that when the negative pressure of I the vacuum is nil, orsubstantially so, during operation of the engine, the bowl 2 will remainin its uppermost position, as illustrated, by action of the spring I6,and this position is predetermined increases sufficiently to counteractthe expansive action of the spring IE, it will draw downwardly thechamber 2 of the carburetor, thus instantly lowering the level of thefluid supply in relation to the mixing chamber and proportionatelydecrease the supply of fuel thereto, thereby preventing unburned orpartially burned fuel from being exhausted from the engine.

In Fig. 2, at 2| is illustrated the upright conducting chamber of theidling jet which is wholly externally of the mixing chamber I and isprovided within its connection to the latter with the suitableadjustment and regulating screws 22 and 23. The idling jet is notshownas the relative supply of gas thereto is at all times constant.

Having thus described our invention, what we claim and desiretosecure byLettersBatent, is:

In a carburetor for an internal combustion engine including a bodymember .providing a mixing chamber, a fuel nozzle within said chamber, abracket rigidly secured to said body member, a movable float chamber,upright guiding means on said bracket for said floatschamber, 1

a flexible connection between said float chamber and said nozzle, adiaphragm chamber secured to said bracket beneath the float chamber, adiaphragm within said diaphragm chamber, a stem connecting saiddiaphragm to said float chamber, resilient means for normally "holdingsaid diaphragm and float chamber-in their uppermost position, and meansconnecting said diaphragm chamber to the intake manifoldof said enginewhereby a predetermined manifold suction will lower the float chamberand consequently lower the fuel level in respect to the nozzle in saidmixing chamber,

FRANK SCHAFER.

HERMAN R. SCHAFER.

